Like a chess player setting up an attack, Amazon continues putting together the pieces to take on Apple in the all-digital, on-the-go future.

Sources from both the film and music industries said Amazon is working on creating a cloud locker service that would enable users to store their existing music, film, and book collections, even content not purchased at Amazon, on the company's servers.

The online merchant has yet to obtain all the necessary licenses, but Amazon managers told counterparts at the studios and labels that it could announce the service before all the negotiations are complete, the sources said.